this is very, very difficult to do at a distance. 

I understand I cannot legally require them to respond, unless the notice specifically requires it, like for instance, a notice of entry, but it's making it difficult to manage the property, and I'm not sure how to proceed.

, but very difficult to DIY remote manage.

This is some of the most desirable and difficult to develop real estate in the country, owned and operated by many of the most powerful and affluent individuals and corporations on earth.

I have heard that CA is very competitive and very difficult to find deals in.

Quote from @Collin Hays: From a macro standpoint, cash flow is difficult when servicing debt, at least in the early years. 

It's very cheap and not difficult to maintain bond/license/insurance.

Its also the right sort of thing to do to try and help someone navigate a difficult time. 

If finding a new replacement is more difficult then get your new property under contract first even before your old property closes.  

There are so many IRS restrictions and prohibited transactions within a Solo 401K that it makes it difficult to navigate.